Assemblage Structure of Ichthyoplankton Communities in the Southern Adriatic Sea (Eastern Mediterranean).

Studies based on fish early life stages can provide information on spawning grounds and nursery areas, helping to determine the implications for stock biomass fluctuations of recruitment variability. This study describes the composition, abundance, spatial distribution and differences in day/night vertical distribution of ichthyoplankton in the southern Adriatic Sea. Samples were collected within the framework of the COCONET project (Towards COast to COast NETworks of marine protected areas) from 9 to 18 May 2013 by the R/V Urania, using the electronic multinet EZ-NET BIONESS (Bedford Institute of Oceanography Net Environmental Sampling System). A total of 20 species, belonging to 20 genera and 13 families, were identified. Of the collected larvae, 74.3% were meso- or bathypelagic species, 24.7% were epipelagic and 0.9% were demersal. The community was dominated by Gonostomatidae, followed by Engraulidae, Myctophidae and Photychthaidae. The most abundant species was Cyclothone braueri (45.6%), followed by Engraulis encrasicolus, Ceratoscopelus maderensis, Cyclothone pygmaea, Vinciguerria attenuata and Myctophum punctatum. An inshore/offshore increasing gradient in biodiversity and abundance was observed. Different weighted mean depths (WMDs) were observed for larvae and juveniles. No diel vertical migrations were observed. The high abundance of meso- or bathypelagic species in the upper 100 m confirms the epipelagic zone as an important environment for the development of the larval stages of these fish.

Live Yeast (Saccharomyces cerevisiae var. boulardii) Supplementation in a European Sea Bass (Dicentrarchus labrax) Diet: Effects on the Growth and Immune Response Parameters.

The present study has been aimed at evaluating the effects of the dietary inclusion of the live yeasts, Saccharomyces cerevisiae var. boulardii (LSB) administered at increasing concentrations (0, 100, and 300 mg kg-1 of feed, here referred to as LSB 0, 100, 300) for 90 days, on the health conditions of European sea bass. The main zootechnical parameters, histological and morphological analyses, innate immunity response parameters (intestinal cytokine expression, lysozyme content, spontaneous hemolytic and hemagglutinating activities, antibacterial activities, and peroxidase activity) were measured as fish welfare parameters. LSB did not impair either growth parameters or the morphometric indexes. LSB down-regulated interleukin-1ß transcription in the distal gut of fish treated with 5.4 × 105 CFU g-1 (LSB100) for 21 days. The interleukin-6 mRNA level decreased significantly in the proximal gut for both doses of yeast, after 21 days of feeding; the gene expression of interleukin-6 was significantly lower in the sea bass fed 10.81 × 105 CFU g-1 (LSB300) probiotic. The levels of TNF-α mRNA were not influenced by probiotic supplementation. Increases, although not significant, in the hematological and immunological parameters were also recorded. The data collected in the present study suggests that an LSB-supplemented diet acts on the gut immune system of sea bass by modulating the expression of the key inflammatory genes.

Integrated biomarker responses in European seabass Dicentrarchus labrax (Linnaeus, 1758) chronically exposed to PVC microplastics.

Few studies evaluated long-term effects of polyvinyl chloride (PVC) microplastics (MPs) ingestion in fish. The present study aimed to investigate the integrated biomarker responses in the liver and blood of 162 European seabass, Dicentrarchus labrax, exposed for 90 days to control, virgin and marine incubated PVC enriched diets (0.1 % w/w) under controlled laboratory condition. Enzymatic and tissue alterations, oxidative stress, gene expression alterations and genotoxicity were examined. Additives and environmental contaminants levels in PVC-MPs, control feed matrices and in seabass muscles were also detected. The results showed that the chronic exposure at environmentally realistic PVC-MPs concentrations in seabass, cause early warning signs of toxicological harm in liver by induction of oxidative stress, the histopathological alterations and also by the modulation of the Peroxisome proliferator-activated receptors (PPARs) and Estrogen receptor alpha (ER-α) genes expression. A trend of increase of DNA alterations and the observation of some neoformations attributable to lipomas suggest also genotoxic and cancerogenic effects of PVC. This investigation provides important data to understand the regulatory biological processes affected by PVC-MPs ingestion in marine organisms and may also support the interpretation of results provided by studies on wild species.

Ontogenetic shift and feeding habits of the European hake (Merluccius merluccius L., 1758) in Central and Southern Tyrrhenian Sea (Western Mediterranean Sea): A comparison between past and present data.

The present paper aims to investigate the ecological role of Merluccius merluccius, Linnaeus, 1758, in southern and central Tyrrhenian Sea (GSA 10, Resolution GFCM/33/2009/2 General Fisheries Commission for the Mediterranean), analyzing ontogenetic diet shifts, geographical variations on prey composition, and feeding habits. A total of 734 hake specimens ranging in size between 6 cm and 73 cm (Total Length, TL) were collected in 2018. In order to evaluate ontogenetic shifts in prey composition, samples were divided into five size classes and for each class the quantitative feeding indices have been calculated. The statistical analysis, based on index of relative importance percentage (%IRI), resulted in three trophic groups. The most abundant prey found in the immature hake specimens (size class I) were the Euphausiids, Stylocheiron longicorne and Mysidacea, while for samples with a total length over 10.5 cm were crustaceans and fish. Engraulis encrasicolus was the most abundant fish prey identified, followed by Boops boops and Myctophids. The high presence of Euphausiids, Mysids, Myctophidae, and Sternoptychidae in classes I, II, II, and IV (6-23 cm) showed the relevant role of mesopelagic fauna in hake diets, with an essential organic matter and energy flow from the mesopelagic to the epipelagic environment. Additionally, decapod crustaceans were found in the stomach contents of hakes belonging to class V (with size over 36 cm TL), which is notable considering that our study area includes an important decapod crustacean fishing area.

Intra- and interspecific variability among congeneric Pagellus otoliths.

Otolith features are useful tools for studying taxonomy, ecology, paleontology, and fish biology since they represent a permanent record of life history. Nevertheless, the functional morphology of otoliths remains an open research question that is useful to completely understand their eco-morphology. This study aims to deepen the knowledge of intra- and interspecific variation in sagitta morphology in three congeneric seabreams, to understand how such variability could be related to the lifestyles of each species. Therefore, the sagittae (n = 161) of 24 Pagellus bogaraveo, 24 Pagellus acarne, and 37 Pagellus erythrinus specimens, collected from the south Tyrrhenian Sea, were analyzed using scanning electron microscopy and a stereomicroscope to assess morphometric features, variability between otolith pairs and the external crystalline structure the of sulcus acusticus. Statistical analysis demonstrated that, between the species, variability in sagittal otolith rostral length growth and sulcus acusticus features, correlated with increased fish total length and body weight. Moreover, slight differences between otolith pairs were detected in P. acarne and P. erythrinus (P < 0.05). The results confirm changes in otolith morphometry and morphology between different congeneric species and populations of the same species from different habitats.

Gonadal macrophage aggregates in fish: A preliminary quantitative study in red mullet.

A histological study was conducted in red mullet, Mullus barbatus, collected from two sites characterized by different anthropogenic impacts. The aim of the study was to assess sex-, size-, season- and site-related variation in gonadal macrophage aggregate (MA) size, number, and relative area. Gonadal MAs were most abundant in males than in females. The number of MA was significantly higher in males from the most impacted site in October, with larger individuals showing more MA than smaller ones. MAs were always found in ripe testes, whereas they occurred only in regressing ovaries. These preliminary findings suggest that the presence of ovarian MA in red mullet is most likely related to ovary regression after spawning, whereas the presence of testicular MA is not necessarily associated to gonad regression, and may vary with season, size, and water quality.

Intestinal alterations in European sea bass Dicentrarchus labrax (Linnaeus, 1758) exposed to microplastics: Preliminary results.

This study investigates, for the first time, the intestinal responses of European sea bass Dicentrarchus labrax chronically exposed to microplastics through ingestion. Fish (n = 162) were fed with 3 different treatment diets for 90 days: control, native polyvinyl chloride (PVC) and polluted polyvinyl chloride (PVC) pellets. Intestines were fixed and processed for histological analysis using standard techniques. Histopathological alterations were examined using a score value (from 0 to 4). The distal part of intestine in all samples proved to be the most affected by pathological alterations, showing a gradual change varying from moderate to severe related to exposure times. The histological picture that characterizes both groups especially after 90 days of exposure, suggests that the intestinal functions can be in some cases totally compromised. The worst condition is increasingly evident in the distal intestine of fish fed with polluted PVC pellets respect to control groups (p < 0.05) to different exposure times. These first results underline the need to assess the impact of increasing microplastics pollution on the marine trophic web.

A histological study of ovarian development in the giant red shrimp Aristaeomorpha foliacea (Crustacea: Decapoda: Aristeidae) from the Southern Tyrrhenian Sea (Western Mediterranean).

The reproductive features of the giant red shrimp, Aristaeomorpha foliacea, were investigated in the southern Tyrrhenian sea by experimental trawl sampling. The annual length-frequency distribution showed a multimodal trend in females, ranging between 16 and 67 mm carapace length (CL), and a unimodal trend in males (18-45 mm CL). Mature males occurred in different proportions all year round, while females displayed seasonal maturity (June-September), with a peak in July. Six oocyte developmental stages were identified, the most advanced of which (Pv, postvitellogenic) had never been described before in this species. Ovary development followed a group-synchronous pattern, with the yolked oocyte stock clearly separated from the reservoir of unyolked oocytes, suggesting that A. foliacea is a total spawner, with determinate fecundity. Based upon histological findings, a revision of macroscopic maturity staging employed in Mediterranean bottom trawl surveys (MEDITS) is proposed.

Cigarette smoke extract immobilizes human spermatozoa and induces sperm apoptosis.

Cigarette smoking by the male partner adversely affects assisted reproductive techniques, suggesting that it may damage sperm chromatin/DNA and consequently embryo development. The effects of graded concentrations of research cigarettes smoke extract (CSE) on motility, mitochondrial membrane potential (MMP), chromatin integrity and apoptosis were evaluated in spermatozoa obtained from 13 healthy, non-smoking men with normal sperm parameters, by flow cytometry. CSE suppressed sperm motility in a concentration- and time-dependent manner and increased the number of spermatozoa with low MMP, the main source of energy for sperm motility. In addition, CSE had a detrimental effect on sperm chromatin condensation and apoptosis. Indeed, it increased the number of spermatozoa with phosphatidylserine externalization, an early apoptotic sign, and fragmented DNA, a late apoptotic sign, in a concentration- and time-dependent manner. These effects of CSE were of similar or even greater magnitude to those obtained following incubation with tumour necrosis factor-alpha, a cytokine known for its negative impact on sperm function, used as positive control. Since transmission of smoking-induced sperm DNA alterations has been found in pre-implantation embryos, and this may predispose offspring to a greater risk of malformations, cancer and genetic diseases, men seeking to father a child are recommended to give up smoking.

Candida albicans experimental infection: effects on human sperm motility, mitochondrial membrane potential and apoptosis.

Studies suggest Candida albicans infection has a negative effect on sperm function, including fertilizing ability. Assisted reproduction treatment using spermatozoa from a patient with unrecognized C. albicans infection did not result in fertilization. Preliminary evidence suggested an effect on sperm motility and apoptosis. This study was undertaken to evaluate the effects of experimentally induced C. albicans infection on motility, membrane mitochondrial potential (MMP), chromatin packaging and apoptosis [membrane phosphatidylserine (PS) externalization and DNA fragmentation] of spermatozoa isolated from normozoospermic healthy men. Motile spermatozoa were isolated by swim-up from 13 normal volunteers and exposed to increasing concentrations (0, 1000, 10,000, and 100,000 cfu/ml) of the fungus for 3 and 24 h. C. albicans was isolated from vaginal swabs, after identification, freshly prepared for experiments. Following incubation, sperm motility decreased significantly (P < 0.05 from 10,000 cfu/ml) and spermatozoa with reduced MMP or PS externalization, an early sign of apoptosis, increased in a time- and concentration-dependent manner. Sperm DNA fragmentation and chromatin integrity increased slightly after exposure to C. albicans, but the increase did not reach statistical significance. This study showed that C. albicans infection may decrease the functional competence of spermatozoa by reducing motility and MMP and by promoting molecular apoptosis mechanisms.

Imbalance in seminal fluid MIF indicates male infertility.

Macrophage migration inhibitory factor (MIF) is a ubiquitous cytokine that functions in reproduction and plays an important role in sperm maturation and motility. Here we reveal a correlation between MIF levels in human seminal fluid and fertility status. We identify an abnormal biphasic profile of MIF in the seminal fluid of patients with impaired sperm parameters. Our findings may be of interest for the development of a diagnostic method for fertility status.

Effects of tumour necrosis factor-alpha on human sperm motility and apoptosis.

The aim of this study was to evaluate the effects of tumour necrosis factor-alpha (TNF-alpha) on sperm motility, mitochondrial membrane potential (DeltaPsi), phosphatidylserine (PS) externalization, sperm chromatin packaging quality, and DNA fragmentation. Motile spermatozoa, obtained from 10 normozoospermic men, were incubated with increasing concentrations of TNF-alpha and analyzed 1, 3, 6, and 24 h after incubation by flow cytometry. TNF-alpha decreased total motility 24 h after incubation at 10 ng/mL and progressive motility 3 h after incubation. Accordingly, TNF-alpha reduced sperm DeltaPsi in a concentration- and time-dependent manner. TNF-alpha increased the percentage of spermatozoa with PS externalization from the concentration of 1 ng/mL 1 h after incubation. TNF-alpha produced sperm chromatin and DNA damage in a concentration- and time-dependent manner. In conclusion, these findings may explain the reduction of fertility, secondary to upregulated production of TNF-alpha, in men with urogenital infections.

Experimental Chlamydia trachomatis infection causes apoptosis in human sperm.

BACKGROUND: Chlamydia trachomatis is responsible for a widespread sexually transmitted infection. In men, it is associated with a wide clinical spectrum causing infertility. Furthermore, C. trachomatis serovar E infection decreases motility and increases the number of non-viable sperm. No other effects of C. trachomatis have been reported on sperm despite the crucial role of DNA integrity for sperm function. The aim of this study was to investigate the effects of C. trachomatis on sperm apoptosis. METHODS: Sperm from eight normozoospermic men were incubated with increasing concentrations of C. trachomatis serovar E elementary bodies (EB) for 6 and 24 h. Sperm were then collected to evaluate phosphatidylserine (PS) membrane translocation and DNA fragmentation by Annexin V-propidium iodide staining, TUNEL assay and flow cytometry. RESULTS: After 6 h of incubation, C. trachomatis had no effect on the percentage of sperm showing PS externalization. However, a significant effect on this parameter was observed after 24 h. C. trachomatis also significantly increased the number of sperm with DNA fragmentation both after 6 and 24 h of incubation. CONCLUSIONS: C. trachomatis causes sperm PS externalization and DNA fragmentation. These effects may explain the negative direct impact of C. trachomatis infection on sperm fertilizing ability.

Inhibition of oocyte fertilization by assisted reproductive techniques and increased sperm DNA fragmentation in the presence of Candida albicans: a case report.

The effects of Candida albicans on sperm parameters and the outcome of infertility treatment are unclear. This report describes a lack of fertilization after assisted reproductive techniques and increased sperm DNA fragmentation in an infertile patient with male accessory gland infection due to Candida albicans. He had normal sperm parameters and, therefore, underwent conventional IVF for a female factor of infertility. No spermatozoa or only one spermatozoon per oocyte were found attached to the zona pellucida of the six mature oocytes retrieved. A new semen sample was then requested from the patient to perform intracytoplasmic sperm injection (ICSI) on the same oocytes, but again no fertilization resulted. Candida albicans was detected in the medium where spermatozoa were co-incubated with oocytes and subsequently in the urethral swabs. It did not have any detrimental effect on sperm parameters soon after ejaculation or following separation of motile spermatozoa by swim-up technique. Fertilization failure after assisted reproduction treatment was associated with an increased percentage of motile spermatozoa having chromatin packaging abnormalities, externalization of phosphatidylserine and DNA fragmentation. In conclusion, Candida albicans did not affect sperm parameters, but increased sperm chromatin packaging damage and apoptosis that might have caused fertilization failure after assisted reproduction treatment in this couple.

Globozoospermia is associated with chromatin structure abnormalities: case report.

A recent study has shown normal sperm chromatin structure in a patient with globozoospermia. However, the poor success rate following intracytoplasmic sperm injection (ICSI) with the use of this sperm suggests that sperm nuclear abnormalities may be present. We report here a study of the sperm DNA integrity and chromosome aneuploidy and diploidy rates of a patient with 100% round-headed sperm. The sperm chromatin packaging quality was assessed by using flow cytometry after staining the DNA with propidium iodide. DNA fragmentation, possibly indicative of apoptosis, was evaluated by flow cytometry using the terminal deoxynucleotidyl transferase-mediated fluorescein-dUTP nick-end labelling (TUNEL) assay. The sperm chromosome aneuploidy and diploidy rates were evaluated by fluorescence in-situ hybridization using alpha-centromeric probes for chromosomes 8, 12, 18, X and Y. The patient with globozoospermia had a significantly higher number of sperm with chromatin decondensation (35 +/- 1.1%) and positive for the TUNEL assay (37 +/- 1.7%) compared with that found in four normal controls (4.7 +/- 0.4 and 22.5 +/- 1.2% respectively). In contrast, the total sperm aneuploidy (0.16%) and diploidy (0.05%) rates for the chromosomes studied were within the range found in 14 normozoospermic men. To the best of our knowledge, this is the first case report of round-headed sperm that has shown an elevated number of sperm with abnormal chromatin structure and DNA strand breaks.